Field of the Invention
The present invention relates to a non-volatile memory device such as a flash memory and an erasure method thereof.
Description of Related Art
In the recent non-volatile memory device such as a flash memory, adopting a double patterning technology in order to attain large scale and high density semiconductor microlithography. The double patterning technology is applied to microlithography technology with resolution smaller than 42 nm, a known method exposing a pattern with 2 times of its pitch then exposing it with an offset of merely half of its pitch, and a plurality of methods such as removing unnecessary patterns after applying a process trick such as a spacer process.